Because there are no established measures for prevention of congenital cytomegalovirus (CMV) infection in the United States, the current approach is haphazard and ineffective. The objective of this application is to develop a brief screening and intervention that will be both acceptable to clinic staff and feasible to implement as part of routine clinical prenatal care, and to test whether behavioral intervention for susceptible women can effect behavioral change that is likely to lead to decreased primary CMV infection. Our central hypothesis is that targeted behavioral intervention, using the health belief model of behavior change, will lead to a measurable and durable behavior change that could decrease the risk of maternal CMV infection (and re-infections). We plan to objectively test our hypothesis by pursuing the following specific aims. 1. Establish prenatal clinic-based CMV screening: As part of our ongoing NICHD Maternal Fetal Medicine Units Network clinical trial to prevent CMV infection, we will establish clinic-based screening in several sites in Rhode Island. Using a central laboratory, we will measure maternal CMV IgG, IgM, and IgG avidity. Identification of women at risk for maternal infection (or re-infection) will allow us to engage them in the randomized trial component of this study to estimate the effect of behavioral intervention on CMV risk-reduction behaviors. 2. Evaluate whether provision of screening knowledge and brief behavioral intervention will influence risk-reducing behavior: Using the health belief model of behavioral change, we will conduct a randomized clinical trial in which half the participants will be allocated to an intervention group and half to standard care. In the intervention group, participants will be informed of their CMV serostatus and will undergo behavior modification training, education delivered by non-physician staff, and will receive visual cues. The comparison group will receive standard clinical care and a brochure on prevention of CMV infection. We will measure compliance in behaviors relevant to CMV infection between the groups. 3. Assess the acceptability of behavior intervention, level of stress/anxiety perceived by the participant relative to the intervention, and the feasibility and likelihood of success of a lage scale intervention roll-out: Using a validated stress scale, we will assess participant acceptabiliy of the intervention. Facilitators of and barriers to a widespread program will be identified in clinical settings as well as at the level of the larger health care system. This contribution will e significant because it will test whether screening and targeted intervention are effective ways of changing behavior that could lead to a significant decline in the number of infants congenitally infected with CMV. This project is innovative because it will be the first large-scale, randomized CMV screening and behavioral intervention study undertaken in pregnant women.